I was able to repair my dead display on my Project Tango Tablet using this teardown guide.

I accidentally dropped my Tango Tablet and the display went blank. The only indication that it would still power up was that the display's backlight was still illuminating. You can verify that the tablet is off by holding the power button for about 10 seconds and watching the backlight shut off.
I was able to repair my device by reseating one connection. In the picture below, there is a black colored ribbon cable. This is the only cable I needed to reseat. To get to the cable, unclip the cover from the device using something gentle like a plastic guitar pick. You can remove the cables connected to the cover, but it's easier just to leave it connected and just flop it out of the way. Remove three T5 sized Torx fasteners retaining the 4 inch long "tin" metal bracket. Then remove the 4 inch long black electrical tape. The black ribbon cable is right below that. Reseat it and your device should start working again. I recommend covering it with an extra piece of electrical tape to keep it from working itself free again.